World Bulletin / News Desk
Children and teens who had higher levels of the chemical bisphenol A in their urine were more likely to be overweight or obese th an children with lower levels, U.S. researchers said on Tuesday.
The findings do not prove that BPA, a type of synthetic estrogen, causes children to gain weight. But researchers said hormone-like chemicals co uld be one reason for an increase in childhood obesity, besides diet and exercise.
"Children are uniquely vulnerable to environmental chemicals," said Dr. Leonardo Trasande of New York University School of Medicine, who worked on the study published in the Journal of the American Medical Association.
Trasande theorized that ingesting extra BPA could throw off young people's hormonal balance and disrupt their metabolism.
BPA has already been banned in the United States from baby bottles and sippy cups, but the U.S. Food and Drug Administration has not banned the chemical from aluminum cans and other types of packaging because it has not been definitively shown to cause harm to adults.
Other studies have suggested a link between BPA and higher weight in adults.
Trasande and colleagues analyzed data from a nationwide health and nutrition survey conducted between 2003 and 2008. Nearly 3,000 subjects ages 6 to 19 were weighed, measured and had their urine tested for BPA. They also answered a range of diet and lifestyle questions.
In total, about one-third of the children were overweight and 18 percent were obese.
The researchers found that slightly more than 10 percent of children with the lowest BPA levels were obese, compared to 22 percent of those with the highest BPA levels.
That was after taking into account how much the children ate, their age, race and gender.
Trasande said he was struck by the strength of that link, but it does not mean extra BPA in children's diets was responsible for the extra pounds they were carrying.
There are a couple of other theories, Trasande said.
"Obese children could ingest food that has higher BPA content - it could be what we call reverse causation," he said. Or, they could have higher BPA stored up in their bodies and release more BPA.
"Those are both very plausible explanations," he said.
Of course, an unhealthy diet and poor physical activity "are still the biggest causes of childhood obesity," Trasande said.
Karin Michels, an epidemiologist from the Harvard School of Public Health in Boston, agreed there is "accumulating evidence" that BPA may be linked to obesity and related diseases like diabetes - although most of that research was conducted on animals.
Her own study, which used similar health and nutrition data, found a link between BPA levels in urine and adult weight.
"We still don't really know how safe bisphenol A is," said Michels, who was not involved with Trasande's study.
While more research is underway, Michels said it makes sense to avoid polycarbonate bottles, aluminum cans and other products containing BPA if there are other options.
"I think we should be on the safe side," she said. But, "I don't think we have to panic about it at this point."
A vaccine developed by researchers has shown promising results with a trial tests showing 100% protection against Ebola
Low lying areas in the Sundarbans region has forced many mothers to join fathers away from home to work, leaving little choice for their children but to take refuge in hostels away from family.
World Wildlife Fund communications manager says plan could come to fruition by 2020, but depends on final gov’t approval
Meteorologists expect El Nino effects to delay the rainy season as dry conditions force locals to pray for rain
Hawaii has become the first American state to ban the use of plastic bags.
Gene therapy for cystic fibrosis has for the first time shown slight but significant benefit on lung function, new British research reveals.
A new study has determined that soda drinks are responsible for more than 184,000 deaths with nearly 80% occurring in low to middle income countries
The plight of these urban areas show how dire the coming global freshwater shortage could get.
Coin-sized band analyzes blood glucose levels and releases insulin when needed
A WHO report has found that the use of lindane and DDT are linked to non-Hodgkin lymphoma
Pope Francis has said that the emissions trading is a ploy to allow wealthy emitters to continue their work
Russian sewerage dump is responsible for declining fish stock in the Baltic seas.
A new cancer drug will be tested as part of a joint effort by AstraZeneca and Lilly.
Smart technology and regulation will aid challenges in global power sector, helping to lower the carbon emitted globally.
A deal between the richest nations in the world has been seen as unlikely, as OECD seeks to phase out export credits.
Soon more than 1 billion consumers in developing nations will be able to buy their first air conditioner, increasing energy demand which will impact global warming